Monrovia weather in September

In September, Monrovia sees average daytime highs of 27°C and overnight lows near 24°C, with 530 mm of rain across 29.3 wet days and about 12 hours of daylight. It is the 10th-warmest and 1st-wettest month of the year here.

Day-to-day highs hold fairly steady near 27°C through the month. The sky is clear or mostly clear about 0% of the time in September, and the air most often feels oppressive.

Daylight stretches from about 12 h 06 min at the start of September to 12 hours by month's end. Set against the rest of the year, September is Monrovia's 11th-clearest and 3rd-windiest month. For the whole year in context, see Monrovia's year-round climate.

Daytime high
27°
10th warmest
Overnight low
24°
2nd coldest
Rainfall
530 mm
29.3 wet days
Daylight
12 hours
6:36 AM – 6:39 PM
Cloud cover
85%
11th clearest
Wind
9 km/h
3rd windiest
Solar energy
4.26 kWh/m²
Travel score
3.4
out of 10

Monrovia is capital city of Liberia.

Density
7,941/km²
people per km²
Founded
1822

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 27°C through the month.

A typical September day in Monrovia reaches about 27°C in the afternoon and slips back to 24°C overnight — a 3°C spread between the day's warmth and the night's chill. On most days the high lands between 26°C and 28°C. Set against its neighbours, September runs on par with August and about 1°C cooler than October.

20°23°25°28°30°151015202530
Avg high (°C)Avg low (°C)
12624
22624
32624
42724
52724
62724
72724
82724
92724
102724
112724
122724
132724
142724
152724
162724
172724
182724
192724
202724
212724
222724
232724
242724
252724
262724
272724
282724
292724
302724

How September really feels in Monrovia

Once humidity and wind are folded in, September averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Monrovia weather by month

How September compares with the rest of the year at a glance. September is the 10th-warmest and 1st-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 25°8317.511.74.9
Feb29° / 25°10220.111.84.2
Mar29° / 25°16125.1123.7
Apr29° / 25°20826.312.13.3
May29° / 25°32129.912.33.0
Jun27° / 24°4922912.43.4
Jul26° / 24°41926.812.33.9
Aug26° / 24°49227.212.23.8
Sep27° / 24°53029.3123.4
Oct28° / 24°35930.411.93.4
Nov28° / 24°19227.611.73.4
Dec28° / 24°10523.111.64.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 0% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 6% of September, with mostly cloudy or overcast conditions the remaining 93%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
1496
2595
3595
4595
5595
6595
7595
8694
9694
10694
11694
12694
13694
14694
15694
16694
17793
18793
19793
20892
21892
22892
23892
24892
25892
26991
27991
28991
29991
30991

Chance of precipitation in September

Any precipitation

Monrovia gets around 530 mm of rain over 29.3 wet days in September, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 97% and peaks near 98% on the wettest days.

0%20%40%60%80%100%151015202530
Rain chance (%)
195
295
396
496
596
697
797
897
997
1097
1197
1298
1398
1498
1598
1698
1798
1898
1998
2098
2198
2298
2398
2498
2598
2698
2798
2898
2998
3098

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

Most of September feels oppressive — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, September lands in the oppressive band about 96% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Oppressive (%)Miserable (%)
1991
2991
3991
4991
5991
6982
7982
8982
9982
10982
11982
12973
13973
14973
15964
16964
17955
18955
19955
20946
21946
22946
23937
24937
25937
26928
27928
28928
29919
30919

Wind in September

Winds average 9 km/h in September.

Across September, daily wind ranges from about 8 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
111calm
211calm
311calm
411calm
511calm
610calm
710calm
810calm
910calm
1010calm
1110calm
1210calm
1310calm
1410calm
1510calm
169calm
179calm
189calm
199calm
209calm
219calm
229calm
239calm
249calm
259calm
269calm
278calm
288calm
298calm
308calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 06 min at the start of September to 12 hours by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 6 minutes over September. Sunrise moves from 6:39 AM to 6:34 AM, and sunset from 6:47 PM to 6:31 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.16:396:47
212.16:396:46
312.16:396:46
412.16:396:45
512.16:396:44
612.16:386:44
712.16:386:43
812.16:386:43
912.16:386:42
1012.16:386:42
1112.16:376:41
1212.16:376:41
1312.16:376:40
1412.06:376:40
1512.06:376:39
1612.06:366:39
1712.06:366:38
1812.06:366:37
1912.06:366:37
2012.06:366:36
2112.06:366:36
2212.06:356:35
2312.06:356:35
2412.06:356:34
2512.06:356:34
2612.06:356:33
2712.06:346:33
2812.06:346:32
2912.06:346:32
3012.06:346:31

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.26 kWh/m².

For context, solar energy here swings from a low near 3.89 kWh/m² to a high of 5.44 kWh/m² in March across the year — September's 4.26 kWh/m² sits near the bottom.

024151015202530
Solar energy (kWh/m²)Level
14.0Bright
24.0Bright
34.0Bright
44.0Bright
54.1Bright
64.1Bright
74.1Bright
84.1Bright
94.1Bright
104.1Bright
114.1Bright
124.2Bright
134.2Bright
144.2Bright
154.2Bright
164.3Bright
174.3Bright
184.3Bright
194.3Bright
204.3Bright
214.4Bright
224.4Bright
234.4Bright
244.5Bright
254.5Bright
264.5Bright
274.5Bright
284.5Bright
294.5Bright
304.6Bright
Planning a trip in September

Hazard calendar for Monrovia

In seasonPeak

In September, Monrovia sits inside its rainy season season. The full year is below, with each hazard's peak months called out.

Monrovia's rainy season runs May–October, when most of the year's rain falls.

Monrovia sees seasonal dust haze (February), heaviest in February.

Rainy season
Dust
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is September a good time to visit Monrovia?

Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

3.4
Sightseeing
7th-best month of the year
3.4
Beach & pool
12th-best month of the year

September is a weaker month for outdoor sightseeing in Monrovia.

What to pack for Monrovia in September

From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In September, Monrovia sees daytime highs around 27°C and nights near 24°C. Pack rain gear. Worth having: light clothes. About 29 days see rain.

rain gearlight clothes

Sea temperature near Monrovia in September

The nearest coast averages about 27°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in May at about 29°C and coldest in August near 27°C.

The water stays above 20°C all year — warm enough for a swim any month.

26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan28Tropical
Feb27Warm
Mar27Warm
Apr28Tropical
May29Tropical
Jun28Tropical
Jul27Warm
Aug27Warm
Sep27Warm
Oct28Warm
Nov28Tropical
Dec29Tropical

UV index in Monrovia in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Monrovia peaks around September 16 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 15 at about 8 (very high).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highSep 16UV 13Dec 15UV 8
UV index (midday)Level
Jan10Extreme
Feb12Extreme
Mar13Extreme
Apr12Extreme
May13Extreme
Jun11Extreme
Jul11Extreme
Aug12Extreme
Sep13Extreme
Oct12Extreme
Nov10Very high
Dec8Very high

Air quality in Monrovia in September

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where September falls, not just the annual average.

Air quality in Monrovia is worst in February — around 50 µg/m³ PM2.5 (poor), about 6.3× the cleanest month (September, 8 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0204060JanFebMarAprMayJunJulAugSepOctNovDecPoorModerateGoodModerateFeb 1249 µg/m³Sep 148 µg/m³
PM2.5 (µg/m³)Level
Jan47Poor
Feb50Poor
Mar44Poor
Apr40Poor
May18Moderate
Jun15Moderate
Jul13Moderate
Aug9Good
Sep8Good
Oct10Good
Nov16Moderate
Dec35Poor
Location & terrain

Where is Monrovia?

Monrovia sits at 6.3°N, 10.8°W, 32 m above sea level, in Liberia. The nearest listed city is Harbel, 49 km away.

HarbelKakataTubmanburgBuchananGbarngaKenemaSegbwemaBo

Topography around Monrovia

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Monrovia.

Within 3 km, the terrain around Monrovia has only modest variations in elevation — a maximum elevation change of 75 m around an average of 3 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 75 m; within 80 km, significant variations in elevation — a maximum elevation change of 337 m.

The land around Monrovia is covered by water (58%) and artificial surfaces (24%) within 3 km, water (65%) within 16 km, and trees (55%) and water (39%) within 80 km.

3 km
75 m
16 km
75 m
80 km
337 m
treesshrubsgrasslandartificial surfacesbare terrainwatermangroves
September weather nearby: Harbel 49 km · Kakata 55 km · Tubmanburg 63 km · Buchanan 95 km · Gbarnga 166 km · Kenema 181 km · Segbwema 189 km · Bo 212 km

Liberia travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 0% of US
price level, 2025
GDP per capita
$915
2025
Happiness
4.3 / 10
World Happiness, 2025
Homicide rate
3.1
per 100k, 2012
Road deaths
38.9
per 100k/yr, 2019
Income group
Low
World Bank
Religion
Christian 85%Muslim 12%none 3%Traditional 1%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Monrovia (6.3005°, -10.7969°, elevation 32 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).